Maryland Institute for Applied Environmental Health Theses and Dissertationshttp://hdl.handle.net/1903/10071
Sun, 20 Nov 2016 20:55:54 GMT2016-11-20T20:55:54ZLUNG CANCER IN NEPAL: THE ROLE OF TRADITIONAL TOBACCO PRODUCTS AND COMBUSTION RELATED HOUSEHOLD AIR POLLUTIONhttp://hdl.handle.net/1903/18303
LUNG CANCER IN NEPAL: THE ROLE OF TRADITIONAL TOBACCO PRODUCTS AND COMBUSTION RELATED HOUSEHOLD AIR POLLUTION
Raspanti, Greg Anthony
The burden of chronic diseases such as cancer is increasing in low and middle income countries around the globe. Nepal, one of the world’s poorest countries, is no exception to this trend, with lung cancer as the leading causes of cancer deaths. Despite this, limited data is available on the environmental and behavioral risk factors that contribute to the lung cancer etiology in Nepal. The objectives of this dissertation are to: 1) investigate the ethnic differences in consumption of local tobacco products and their role in lung cancer risk in Nepal; 2) evaluate urinary metabolite of 1,3-butadiene as a biomarker of exposure to combustion related household air pollution (CRHAP); 3) investigate the association between CRHAP exposure and lung cancer risk using urinary metabolite of 1,3-butadiene as a biomarker of exposure; 4) investigate the association between CRHAP exposure and lung cancer risk using questionnaire based measure of exposure.
Lung cancer cases (n=606) and frequency matched controls (N=606) were recruited from B.P. Koirala Memorial Cancer Hospital. We obtained biological samples and information on lifestyles including cooking habits and type of fuels used. We used liquid chromatograph tandem mass spectrometer (LC-MS/MS) to quantify urinary metabolites of 1,3-butadiene in urine samples. We employed a combination of logistic and linear regression models to detect any exposure-disease associations while controlling for known confounding variables.
Overall, we found that ethnic groups in Nepal use different tobacco products that have different differing cancer potency -we observed the highest odds ratios for the traditional tobacco products. The biomarker analysis showed strong evidence that monohydroxybutyl mercapturic acid is associated with biomass fuel use among participants. However, we did not find significant association between urinary MHMBA and lung cancer risk. When we used questionnaire based measure of exposure to household air pollution, we observed significant, dose-response associations between CRHAP exposure and lung cancer risk, particularly among never-smokers.
Our results show that important role of local tobacco products in lung cancer risk in Nepal. Furthermore, we demonstrate that CRHAP exposure is a risk factor for lung cancer risk, independent of tobacco smoking.
Fri, 01 Jan 2016 00:00:00 GMThttp://hdl.handle.net/1903/183032016-01-01T00:00:00ZImpact of Cryptosporidium spp. interaction with co-occurring microorganisms on moderate-to-severe diarrhea in the developing worldhttp://hdl.handle.net/1903/18120
Impact of Cryptosporidium spp. interaction with co-occurring microorganisms on moderate-to-severe diarrhea in the developing world
Reid, Molly Carroll
Diarrheal illness is responsible for over a quarter of all deaths in children under 5 years of age in sub-Saharan Africa and South Asia. Recent findings have identified the parasite Cryptosporidium as a contributor to enteric disease. We examined 9,348 cases and 13,128 controls from the Global Enteric Multicenter Study to assess whether Cryptosporidium interacted with co-occurring pathogens based on adjusted odds of moderate-to-severe diarrhea (MSD). Cryptosporidium was found to interact negatively with Shigella spp., with multiplicative interaction score of 0.16 (95% CI: 0.07 to 0.37, p-value=0.000), and an additive interaction score of -9.81 (95% CI: -13.61 to -6.01, p-value=0.000). Cryptosporidium also interacted negatively with Aeromonas spp., Adenovirus, Norovirus, and Astrovirus with marginal significance. Odds of MSD for Cryptosporidium co-infection with Shigella spp., Aeromonas spp., Adenovirus, Norovirus, or Astrovirus are lower than odds of MSD with either organism alone. This may reduce the efficacy of intervention strategies targeted at Cryptosporidium.
Thu, 01 Jan 2015 00:00:00 GMThttp://hdl.handle.net/1903/181202015-01-01T00:00:00ZMonitoring and Assessment of Residential Exposure to Noise Associated with Natural Gas Compressor Stations in West Virginiahttp://hdl.handle.net/1903/15965
Monitoring and Assessment of Residential Exposure to Noise Associated with Natural Gas Compressor Stations in West Virginia
Boyle, Meleah
Noise is a growing concern for residents living near natural gas compressor stations. This study monitored and evaluated residential noise exposure associated with living near natural gas compressor stations in West Virginia. Short-term outdoor measurements (20 min) and medium-term (24-hour) indoor and outdoor measurements were collected at homes located near compressor stations. The average sound equivalent was calculated using logarithmic averages and stratified by distance from compressor station, time of day, and location. Average short-term noise levels were 61.43 dBA (45.3 to 76.1 dBA); average 24-hour noise levels were 60.20 dBA (35.3 to 94.8 dBA). Average noise levels at control homes were 51.40 dBA, with 45.02 dBA indoors and 54.03 dBA outdoors. Average noise levels at homes near compressor stations were 8.7 dBA higher, with a 16.25 dBA difference indoors and a 4.3 dBA difference outdoors. Results indicate that living near a natural gas compressor station may increase environmental noise exposure.
Wed, 01 Jan 2014 00:00:00 GMThttp://hdl.handle.net/1903/159652014-01-01T00:00:00ZIMPACT OF RURALITY, BROILER OPERATIONS, AND COMMUNITY SOCIOECONOMIC FACTORS ON THE RISK OF CAMPYLOBACTERIOSIS IN MARYLANDhttp://hdl.handle.net/1903/15108
IMPACT OF RURALITY, BROILER OPERATIONS, AND COMMUNITY SOCIOECONOMIC FACTORS ON THE RISK OF CAMPYLOBACTERIOSIS IN MARYLAND
Zappe Pasturel, Barbara
The combined impact of community-level environmental and socioeconomic factors on the risk of campylobacteriosis were evaluated. Campylobacter case data (2002-2010, n=3,694) were obtained from the Maryland Foodborne Diseases Active Surveillance Network. Community-level socioeconomic and environmental data were obtained from the 2000 U.S. Census and the 2007 U.S. Census of Agriculture. Data were linked by zip code. Incidence rate ratios were derived by Poisson regressions. A subset of zip code-level characteristics was mapped. In zip codes that were 100% rural, incidence rates of campylobacteriosis were 6 times (IRR=6.18; 95%CI=3.19-11.97) that of urban zip codes. In zip codes with broiler chicken operations, incidence rates were 1.45 times that of zip codes without broilers (IRR=1.45, 95%CI=1.34-1.58). Higher rates were also observed for zip codes that were predominantly white and had high median incomes. Findings suggest that the risk of campylobacteriosis could be significantly influenced by the community and environment where one lives.
Tue, 01 Jan 2013 00:00:00 GMThttp://hdl.handle.net/1903/151082013-01-01T00:00:00Z